oracle sql 澄清在 where 子句中使用 case 条件，错误 sdo_nn 无法在没有索引的情况下进行评估

Question

我正在使用带有 oracle 空间的 oracle 11g，如果我在 where 条件中使用如下距离，则此查询有效

mdsys.sdo_nn ( b1.location, l_location , 'SDO_BATCH_SIZE=100 distance='|| 
c1.tier_radius||' unit=KM', 1) = 'TRUE'

但是我希望根据条件评估距离。下面的查询给出了错误 sdo_nn 无法在没有索引的情况下进行评估，我希望根据类似这样的条件评估距离

select
        /*+ first_rows LEADING(c) USE_NL(c1 b1) INDEX(b1 BRANCH_LOCATION_SPIX)*/
        b1.BRANCH_ID,
        mdsys.sdo_nn_distance(1) branchDistance
      from
        branch b1, city c1
      where
        mdsys.sdo_nn ( b1.location, l_location , 'SDO_BATCH_SIZE=100 distance='|| (case  when b1.restaurant_id not in (3970,3971,3972) then c1.tier_radius
        else 15 end) ||' unit=KM', 1) = 'TRUE'   
        and b1.city_id = c1.city_id  

Answer 1

我们知道那部分

mdsys.sdo_nn ( b1.location, l_location , 'SDO_BATCH_SIZE=100 distance='|| 
c1.tier_radius||' unit=KM', 1) = 'TRUE'

有效，那么我认为您可以使用包含union all 的查询，如下所示：

select  /*+ first_rows LEADING(c) USE_NL(c1 b1) INDEX(b1 BRANCH_LOCATION_SPIX)*/
        b1.BRANCH_ID,
        mdsys.sdo_nn_distance(1) branchDistance
  from branch b1 
  join city c1 on c1.city_id = b1.city_id
 where mdsys.sdo_nn ( b1.location, l_location , 'SDO_BATCH_SIZE=100 distance='||c1.tier_radius||' unit=KM', 1) = 'TRUE'
   and b1.restaurant_id not in (3970,3971,3972)
union all
select  /*+ first_rows LEADING(c) USE_NL(c1 b1) INDEX(b1 BRANCH_LOCATION_SPIX)*/
        b1.BRANCH_ID,
        mdsys.sdo_nn_distance(1) branchDistance
  from branch b1 
  join city c1 on c1.city_id = b1.city_id
 where mdsys.sdo_nn ( b1.location, l_location , 'SDO_BATCH_SIZE=100 distance=15 unit=KM', 1) = 'TRUE'
   and b1.restaurant_id in (3970,3971,3972)